1. Field
The following description relates to an optical transmission technology, and more particularly, to an optical waveguide and a bi-directional optical transceiver.
2. Description of the Related Art
FIG. 1 is a view illustrating a conventional bi-directional optical transceiver, which performs a bi-directional optical communication using a single optical waveguide such as an optical fiber. The bi-directional optical transceiver 1 includes an optical waveguide 10, an external filter 20, a light generation unit 30 and a light detection unit 40.
The optical waveguide 10, for example, an optical fiber, is a transmission line including a core 11, an optical fiber for transmitting light and a cladding 12 surrounding the core 11 to confine light in the core 11 through total internal reflection.
The external filter 20 is configured to divide bi-directional signals, which travel in opposite directions, in a manner that a transmission light is refracted while passing through the external filter 20 and a reception light is reflected and thus travels in a different path.
The light generation unit 30 is configured to transmit light and may be provided as a laser diode (LD) for transmitting light to the optical waveguide 10.
The light detection unit 40 is configured to receive light and may be provided as a photo diode (PD) for detecting light from the optical waveguide 10.
A transmission signal is output in the form of an optical signal, which is converted from an electrical signal by the light generation unit 30. The transmission signal passes through the external filer 20 and then is transmitted through the core 11 of the optical waveguide 10.
A reception signal is received through the core 11 of the optical waveguide 10 and reflected by the external filter 20 and thus travels in a different path. After that, the reception signal provided in the form of an optical signal is converted to an electric signal by the light detection unit 40. In that manner, a bi-directional communication through a single optical waveguide 10 is achieved.
However, since the bi-directional optical transceiver is implemented based on using free space optics system, in which optical signals are divided by the external filter 20 installed among the optical waveguide 10, the light generation unit 30 and the light detection unit 40, the performance of the optical transceiver is dependant on the position of components of the optical transceiver.
In particular, the optical components need to be manually aligned such that transmission signals output from the light generation unit 30 pass through the core 11 having a very small diameter. However, the use of the external filter causes difficulties in aligning the optical components and realizing a compact sized bi-directional optical transceiver.
In this regard, a study has been pursued to provide an optical waveguide and an optical transceiver, in which the manual alignment of optical components are easily achieved and thus that can be miniaturized and can effectively transmit and receive light by facilitating a manual alignment for optical components.